Philippine police on Sunday urged fishermen and residents of coastal communities to be on the lookout for bricks of cocaine being thrown near their shores as a way to smuggle the illegal drug into the country.

The call was made after fishermen and residents from three towns along the country's eastern coast turned over more than 60 bricks of cocaine to authorities over the past week.

The bricks, in various sizes, were recovered from the sea off the islands of Dinagat and Siargao on Tuesday and Thursday, police said.

On Saturday, a brick weighing almost 1 kilo was recovered off the shore of Paracale town in Camarines Norte province, 194 kilometres south-east of Manila, and turned over to police.

‘We continue to call on all residents of all our coastline communities across the nation, including all fishermen and seafarers to remain vigilant and continue reporting to the police suspicious items they may find washed ashore or floating in the sea,’ national police said in a statement.

‘Your active participation in our anti-illegal drugs law enforcement operations and maintenance of peace and order continues to inspire us in performing our mandate as provided by law to fight illegal drugs with utmost respect for human rights,’ the statement added.

The administration of President Rodrigo Duterte has been waging an aggressive campaign against drugs, in which more than 5,000 people have been killed since 2016.

The New York-based watchdog Human Rights Watch said the true death toll of the drug crackdown, including victims of hired or vigilante killers, could be higher than 12,000, based on estimates by local rights and church groups.